Detection of ultra-high-energy cosmic rays in the southern hemisphere with FAST: data acquisition and preliminary results

Jakub Kmec; Petr Boril; Fraser Bradfield; Karel Cerny; Ladislav Chytka; Toshihiro Fujii; Pavel Horvath; Miroslav Hrabovsky; Vlastimil Jilek; Jiri Kvita; Max Malacari; Massimo Mastrodicasa; John N. Matthews; Stanislav Michal; Marcus Niechciol; Libor Nozka; Miroslav Palatka; Miroslav Pech; Paolo Privitera; Francesco Salamida; Shunsuke Sakurai; Petr Schovanek; Radomir Smida; Zuzana Svozilikova; Haruka Tachibana; Akimichi Taketa; Stan B. Thomas; Petr Travnicek; Martin Vacula; Jiri Zahora; Dusan Mandat; Petr Hamal

arXiv · 2510.20522

Detection of ultra-high-energy cosmic rays in the southern hemisphere with FAST: data acquisition and preliminary results

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Abstract

Ultra-high-energy cosmic rays (UHECRs) remain one of the greatest mysteries in astroparticle physics. The Fluorescence detector Array of Single-pixel Telescopes (FAST) is a next-generation cosmic ray experiment which utilizes ground-based fluorescence telescopes designed to detect these extremely rare particles at energies exceeding 30 EeV. FAST offers a cost-effective and low-maintenance solution to cover the huge detection areas required for UHECR observation. FAST telescopes are currently installed and remotely operated in both hemispheres, at the Pierre Auger Observatory and the Telescope Array experiment. To enable fully autonomous operation, a sophisticated trigger for data acquisition is essential. In this paper, we present two novel triggering algorithms inspired by those used at the largest observatories, but improved to meet the specific requirements imposed by the FAST design. Their performance is validated using Monte Carlo simulations of extensive air showers and UHECR events detected by the FAST telescope in the southern hemisphere. Finally, we present the sensitivity analysis estimate for FAST.

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Jakub Kmec, Petr Boril, Fraser Bradfield, Karel Cerny, Ladislav Chytka, Toshihiro Fujii, Pavel Horvath, Miroslav Hrabovsky, Vlastimil Jilek, Jiri Kvita, Max Malacari, Massimo Mastrodicasa, John N. Matthews, Stanislav Michal, Marcus Niechciol, Libor Nozka, Miroslav Palatka, Miroslav Pech, Paolo Privitera, Francesco Salamida, Shunsuke Sakurai, Petr Schovanek, Radomir Smida, Zuzana Svozilikova, Haruka Tachibana, Akimichi Taketa, Stan B. Thomas, Petr Travnicek, Martin Vacula, Jiri Zahora, Dusan Mandat, Petr Hamal. 2025-10-23. Detection of ultra-high-energy cosmic rays in the southern hemisphere with FAST: data acquisition and preliminary results. https://arxiv.org/abs/2510.20522

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